Stretching apparatus



A. L. RUSSELL.

STRETCHING APPARATUS. APPLICATION FILED FEB. 11. ms.

Patented July 13, 1920.

UNITED, STATES PATENT OFFICE. l"

ARTHUR L. RUSSELL, OF BOSTONyMASSACHUSETTS, ASSIGNOB TO UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

STRETCHING APPARATUS.

Specification of Letters Patent.

Patented July 13, 1920.

Application filed February 11, 1918. Serial No; 216,481.

To all whom it may concern.-

Be it known that I, ARTHUR L. RUssnLL, a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain 1m provements in Stretching Apparatus, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the several figures.

This invention relates to apparatus for stretching various sheet materials, as leather, and particularly to such apparatus for producing fullness in material over predetermined areas, as in the calf portion of blanks which are to-be formed into leggings.

In work of this character, especially with certain grades of stock, the finished shape of the article may be more readily and perfectly obtained by subjecting the blank, as a preliminary to the final forming, to a stretching operation over the portions of most abrupt curvature. The present invention provides apparatus for this purpose, simple in construction and efficient in action, in which ample power is supplied for the stretching operation while permitting the area operated upon to be varied quickly to give the shape sought.

A feature of the invention consist in a form having sections movable relatively to one another from a source of power to cause their successive separation and approach, over which sections thematerial operated upon is placed to be stretched by the movement and to be shifted during such movement to vary its effect. In the illustrated embodiment of the invention, the form gen erally resembles a portion of the surface over which the finished article is to fit, the sections being furnished by two similarly shaped, supplementary members having adjacent edges which recede from and approach one another under the influence of the power drive. The work-engaging S11I'-' faces are inclined with respect to one another, diverging outwardly to opposite separated edges, said surfaces preferably being curved.

As another feature of the invention, the engaging members are provided with means to prevent the workfrom slipping bodily over them during their recession. That this retaining engagement with the work may not interfere with its ready positioning to control the area operated upon, the retaining means cooperates with the hands of the operator, being here shown as furnished by the separated edges of the form over which the material is bent and grasped by the operator. Material engaging projections extending along these edges may also be provided, to aid in retaining in place the outer edges of the stock during its stretching.

A further feature is found in means with whichthe stretching members are provided for extending the stretching action over the surfaces of the members. 7 This means is preferably applied near points at which the members separate to tension the material, and may consist conveniently of projections lying along the adjacent edges of the mem bers to contact with the material over limited areas and raise it above the surfaces of the members for some distance outwardly.

The above and other features are hereinafter described in detail in connection with the accompanying drawings, in which,

Figure 1 is an end elevation of one form which my apparatus may assume, parts being broken away, and

Fig. 2 is a section on the line 2-2 of Fig. l, the housing and one of the stretching members being broken to show the operating connections.

The main frame of the apparatus may be furnished by a housing 10 rising from a base 12 arranged for attachment to a bench or other support. The housing incloses the motive elements of the apparatus and has at the top of the opposite side walls upward extensions 14, 14. These extensions carry stretching members which are movable relatively to one another. In Figs. 1 and 2 of the drawings, one member 16 is shown as integral with the extensions 14, while the other member 18 is pivoted upon the extensions to oscillate toward and from its companion, their upper work-engaging surfaces 20, 20 being inclined or diverging down wardly from adjacent meeting edges 22, 22 to opposite edges 24;, 24. I prefer to have the stretching members furnished by similarly shaped sections of a contour generally similar to a portion of the object over which the finished work is to fit. The apparatus here disclosed is adapted for stretching the calf portion of legging blanks, the form sections resembling the opposite vertical halves of the rear calf portion of a leg, they being each curved transversely through about 90 from the adjacent meeting edges tion of the knee and ankle, respectively.

I have shown the form sections as consist ing of hollow castings open at the bottom. The member 16 has vertleal'webs 32-con tinuing the frameextensions. In the extensions 14:, 14-, at their juncture with the webs be a tendency to somewhat sharply localize 32, are horizontally-alined, separable studs 33, 83 to enter openings in lugs 34, Snear theendsof'the form section 18. Pivots-d upon opposite webs 36, 36 projecting into the interior of the sections are toggle links 38, 38, the central articulation which joined by a link 40 to a pin42 of a crank disk 44. This disk is fixed to the end'of a shaft 46 journaled inia bearing on the frame base and in one of the housing'walls, Van-l has fast upon it a pulley l8 through which the apparatus may be continuously driven" from any suitable source of power to cause, by the straightening and breaking of the toggle, the form section 18 to move fromand toward the section 16.

To retain the material to be operated upon in placev on the form sections so. that it may be stretched by their separation, the lower edges 24,-, 24: have means for resisting the bodily slipping of the material over the engaging surfaces 20 under thestretchin tension. It is desired that this resist cc to movement shall beattained while leaving the material free'to be shifted readily for the presentation of new areas t be stretched. To this end, the retainingmeans may be furnished in whole or in part by the depending edges 24 themselves, they giving longitudinally extending projections over which bights of the materials may be turned and vgrasped by the operatofis hands, as illustrated in Fig. 1'. Afurther retainingmcans is also shown inroughencd surfacesat the outer lower portions of the engaging surfaces 20, there being series'of projections 50, preferably pointed or 'V-sha pod, with inter mediate groovesslying parallel to the edges 24 of the sections. 1 Against these projections the material may be forced by the hands of the operatoigso that movement of itsouter edges is resisted. It is to be noted that this retention of the'material' is not necessarily positive,but that it slip to some extent and still be effectively stretched; In fact, by varying thefirmness of his grasp uponthe work, the operator may control'tho amount of fullness imparted;v i

In absence of means for distributing or extending the stretching action, there would.

it between the points of maximum separafacts with the surfaces 20.

tion of the edges 22 of the members, this being due to the frictional engagement 7 of the surfaces 20 with the material; resisting stretching movement over them. To; prevent this,1I'mayprovide some such means asprojections 52, 52, preferably rounded at their extremities, extending outwardly along the edges 22, These projections act against the material by theirsmooth narrow surfaces, and therefore with slight frictional resistance, to raise it from the surfaces 20, as indicated at: in Fig. 1, and cause the stretching action of the movable sections to'be elfectively applied to these portions of the work over the form surfaces beyond the edges 22.

In using the apparatus of this invention for stretching the calf portion of, legging blanks, the sheet 5 of legging material,

properly tempered, is laid'acrossthe form sections, said material at each sideextending below the section edges 24. hen the, edges 22 of the sections most closely approach one another, as the apparatus is continuously driven from the power-shaft t6,'the material is grasped by the operator, who turns-it under the edges 24: of the sections and forces it against the projections 50 to hold this portion of the material from slipping. The horizontal arrangement of the form renders this positioningof the material and its further manipulation easy} As the sections separate, that portion of the blank over and adjacent to the portion 26 of the form is stretched, the maximum effect being exerted between the edges 22,. with a somewhat less action upon the material raised from the form by the projections 52 and a gradual diminution of stretching outwardly through the material which con- Longitudinally of the form, since the radial distance of the adjacent edges of the portions26 from the axis of oscillation diminishes oppositely from their centers, the maximum movement of separation willbe at said centers, and a corresponding stretching effect will be obtained. In this way the material is successively tensioned as'a result of the alternate recessions 'andapproaches of the sections. As the elasticity ofthe material lessons in stretching, the operator may take up the slack in the blank'by drawing it more tightly over theform as the sections approach, ormay shift it either laterally or longitudinally upon the form, each time grasping it anew to hold it against slipping; This continues until a suflicientfullness of the blank over the desired area has been obtained, whenthc stretched material is removed and the apparatus is ready for another operation.

Having thus described my invention, what Iclaim as new and desire to secure by Letters Patent of thellnited States is:

1. In a stretching apparatus, a form consisting of a plurality of relatively movable sections over which the material to be stretched may be placed, and power-operated means arranged to cause Successive separations and approaches of the sections to effect the stretching of each piece of work, the

form being constructed and arranged to permit the-material to be shifted over the sections during their successive movements.

2. In a stretching apparatus, a form consisting of a plurality of relatively movable sections over which the material to be stretched may be placed, and continuously operated means for effecting successive recessions and approaches of the sections.

3. In a stretching apparatus, two rela tively movable stretching members associated vto furnish a convex work-engaging surface, and continuously operating means for effecting successive recessions and approaches of the members to gradually stretch the work. 7 1

In stretching apparatus, a form consisting of two similarly shaped relatively movable sections over which'the material to be stretched may be placed, said sections having edges arranged to hold the work in stretching engagement under the influence of the hands of the operator, and power-operated means forseparating the sections to effect the stretching.

5. In a stretching apparatus, a form con sisting of a plurality of relatively movable sections over which the material to be stretched may be placed,-the sections having portions arranged for such engagement with the material as to resist its slipping bodily upon said portions during the stretching op eration, and power-operated means for mov ing the sections. a

6. In a stretching apparatus, a form consisting of a plurality of relatively movable sections over which the material to be stretched may be placed, and means for ef' fecting successive recessions and approaches of the sections, the form sections having portions arranged for uch engagement with the material. as to retardits slipping upon such portion during the recessions of the sections yet permitting said material to be shifted readily during the approach of the sections.

7. In a stretching apparatus, a form consisting of a plurality of relatively movable sections over which the material to be stretched may be placed, and means for separating-the sections to effect the stretching, said sections having means for extending the stretching action over the surface of the form from the points of separation.

8. In a stretching apparatus, a form consisting of a plurality of relatively movable sections over which the material to be stretched be placed, and means for separating the sections-to effect the stretching, said sections having means to hold the ma opposite edges of the legging material may respectively be placed, and power-operated means for separating the surfaces whlle the material is held in stretching engagement with both. I

10. In a stretching apparatus for legging material, a form provided with two relatively movable material-engaging surfaces generally similar in shape to a portion of a leg and in contact with which the legging material may be placed, and continuously operating means for moving the sections toward and from one another, said sections being constructed and arranged to permit the'material to be held in stretching engagement during'their recession and to be shifted readily to present another area for stretching during approach.

11. In a stretching apparatus,relatively movable members having opposite separated edges arranged to engage the material to be stretched when this is pressed against them by thehands of the operator and resist its bodily -movement under the stretching action.- V

12. In a stretching apparatus, a support for the material to be stretched consisting of relatively movable sections situated with edges adjacent one another while other edges of the respective sections are separated, said separated edges beingarranged to engage the material turned over them to resist its movement when grasped by the operator.

13. In a stretching apparatus, relatively movable stretching membershaving workengaging surfaces with adjacent edges, there being work-engaging projections extending beyond the work-engaging surfaces at the edges of the members.

14. Ina stretching apparatus, relatively movable stretching members; having workengaging'surfaces inclined to one another and converging to adjacent edges at which are work-engaging projections.

15'. In a stretching apparatus, relatively movable stretching members having workengaging surfaces inclined to one another and converging to adjacent edges at which are work-engaging projections, and means at the opposite edges to assist the operator to manually retain the workupon the members.

16. In a stretching apparatus, relatively movable stretching members having workengaging surfaces inclined to one another and convergingto adjacent edges at which are work-engaging projections, there being work-engaging means at the opposite edges of the members.

.ing surfaces along the edges.

17. In a stretching apparatus, a form cons1stmg of relatively mo'va'ble work-engaging sections one ofwhich is pivotally mounted, a

power shaft, and connections from the power shaft to the pivoted member to oscillate said member to stretchthe work. i r

18. Ina stretching apparatus, a form consisting of relatively movable work-engaging sections one'of which is pivotally moimted, a

-power shaft, :a toggle connecting the 'sect1ons,- and a connection between the toggle and the power shaft. r r

j ,19. In a stretching apparatus, a frame, a form sectlon fixed upon the frame, a cooperating andsimilarly shaped form sec- 7 tion pivoted on'the frame, a toggle connecting the sections, a power shaft-journaled in the frame, and connectlons between the power shaft and toggle. j V

20. In a stretching apparatus, a *frame,

relatively movable stretching members extending upwardly from the frame, said members having ad acent edges and being provided with work-engaging surfaces inclined outwardly and downwardly from said edges,-a power shaft, and connections from the power shaft to the stretching ,members.

211' In a stretching apparatus, a frame,

relatively movable stretching members extending fromthe frame, saidmembers having adjacent edges and being provided with work-engaging ,surfaces curved outwardly from and along saidredges, apower shaft, and connections fromthe power shaft to the stretching members.

7-22. 111F214 stretchin apparatus, a frame,

and. stretching members extending upwardly from-the frame, said members having adja' cent edges ,and beingprovided with workengaging surfaces inclined outwardly-and downwardly from-said edges, -there be ng upward projections above the work-engag- 23, In a stretching apparatus, a-frame,

] and stretching membersextending upwardly from-the frame, saidmembers having adj acent-edges and being provided with-workengaging, surfaces inclined outwardly and downwardly from said edges, the 1 opposite or loweredges being formed to resist bodily movement of the work under the stretching action; v

-24. Ina stretching apparatus, relatively movable stretching members having workengaging surfaces, there being projections from themembers holding the work away over limited areasifrom the general workengaging surfaces. 7 i Y 125. Ina stretching apparatus, a support for the material to be stretched consisting 10f relativelymovable sections situated with edges adjacent, there being projections extending song said adjacent edges.

26.111 a stretching apparatus, a frame,

and relatively movable" stretching members extending upwardly from the frame, said members having'ad acent edges and being provided with work-engaging surfaces 1nclinedoutwardly and downwardly from said edges, the opposite or lower portions of' the members having work-engaging projections extending transversely to the direction of stretchlng movement.

ing supplementary sections arrangedfor relative oscillatory movement and being provided with work-engaging surfaces curved from adjacent edges in the direction of oscillation andalso transversely thereto.

80. A form for a stretching apparatus having relatively movable sections provided with work-engaging surfaces inclined from adjacent edges at which edges are work-V engaging i projections. v

31. A form for a stretching apparatus having relatively movable sections provided with work-engaging surfaces inclined from ad acentedges to opposite edges at which opposite edgeslare means tendlng to resist bodily movementofthe i work over the sec;

tions. 7 325A form for a stretching apparatus having relatively movable sections provided with work-engaging surfaces inclined from adjacent edges vto opposite edges along which opposite edgesare a plurality .of work-engaging pro ections.

38. A form for a stretching apparatus having sections relatively movable about an axis longitudinal of the form and provided with work-engaging surfaces situated at different radial distances from said axis.

34. In a'stretching apparatus, a form consisting of a pluralityof relatively movable sections over which -the,material to be stretched (may be placed 7 and automatic meansforeffecting repeated recessions and approaches of the sections;

I In testimony 'whereofI have signed my name to this specification.

ARTHUR L. RUSSELL. 

